Towards fixing no_roll()

Currently ::roll() may actually be a ::no_roll() under some circumstances.

This can also happen during count-in:
  transport_stopped () == transport_rolling()

and during latency-preroll:
   Global session-transport speed != 0, some tracks already roll,
   read data from disk and feed latent plugins.
   but other non-latent tracks or busses don't roll and still have to
   behave like the switch from no_roll() to roll() has not yet happened.

This changes the game WRT to monitoring as well, previously, Route:roll()
called Route::no_roll_unlocked () for conditions outlined above.
Now Track::no_roll_unlocked is called and in some cases wrongly clears
the buffers before the signal hits the disk-writer. (more work is needed
related to 61f8e53b)

On the upside this also fixes an issue with MidiTrack::no_roll not keeping
a lock while pushing data into the step-edit-ringbuffer.

This is also a step towards consolidating all entry points:
::roll(), ::no_roll(), ::silent_roll() in the Route class.

0 files changed, 0 insertions, 0 deletions